The present invention relates to a continuous-form sheet guide mechanism for a printer in which an image is formed on the continuous-form sheet, by the so-called electrophotographic processes and which is capable of being folded at a certain interval of length, and more particularly to a guide mechanism for controlling a direction along which the continuous-form sheet is discharged from the printer.
Imaging devices, such as laser printers have recently been widely used, in which a laser beam is modulated in accordance with graphics, characters and other image information is scanned on a surface of an electrically charged sensitized body (for example, photoconductive drum) for exposure to form a electrostatic latent images, and which is then developed to a visible image and transferred and fixed by a duplication processes (so-called electrophotographic processes), to thereby obtain a hard copy carrying image information on the continuous-form sheet. Small and inexpensive apparatuses using semiconductor lasers have been vigorously commercialized.
While such laser printers or the like image formation apparatuses sometimes use cut-sheet type recording sheets having a certain size, continuous-form sheet capable of being folded at a predetermined interval of length, so-called fan-folded sheet, is more often used to allow them to deliver hard copies with image information consecutively at a high speed. The fan-folded sheet is used as such continuous-form sheet. The fan-folded sheet has sprocket holes provided along a longitudinal direction at a certain interval of pitch on both sides of the sheet width, with a widthwise extending perforation at each folding line spaced by a certain interval of length with each other.
When using the continuous-form sheet, such as the fan-folded sheet, the continuous-form sheet is heated and pressed, i.e., thermally pressed by heat rollers as part of a fixing unit of the imaging devices. This causes folding lines at the perforations to tend to disappear, making folding operations difficult.
Since the folding lines of the continuous-form sheet are eliminated by the thermal press in the fixing process, causing trouble in the folding operations, the continuous-form sheet, that should have been stacked in a neatly folded state after being discharged from the imaging device, is likely to be placed in a sort of mess around a discharge outlet of the continuous-form sheet.